Someone is literally taking potshots at military locations, and now the FBI has announced it will investigate.

Ballistics testing from recent early-morning shootings at the Pentagon and the National Museum of the Marine Corps show a single weapon was used in both incidents. There was another overnight shooting on Oct. 25 or 26 at the Marine Corps Recruiting station in Chantilly, Va. Ballistics testing is now underway to see if those shots also came from the same weapon.

No one was injured in the pre-dawn shootings, and the shooter seems to be targeting buildings, not people. Officials say they are taking the incidents seriously, but point out that no one is sure if the incidents are anything more than vandalism by gun.

An internal sweep of the building was conducted, and that's when two rounds were found to have struck the building on the side that faces I-395. That led Pentagon security to request the closure of the highway so that they could look for rounds or shell casings that may have been left behind, along the side of the road. Ballistic evidence found at the scene matched evidence found at the Marine Corps Museum.

The FBI said no further information, including a potential weapon used or the caliber of the ammunition, will be released at this time to preserve the integrity of investigative efforts.